Spatially-resolved potential measurement with ion crystals

We present a method to measure potentials over an extended region using one-dimensional ion crystals in a radio frequency (RF) ion trap. The equilibrium spacings of the ions within the crystal allow the determination of the external forces acting at each point. From this the overall potential, and also potentials due to specific trap features, are calculated. The method can be used to probe potentials near proximal objects in real time, and can be generalized to higher dimensions.Comment: 7 pages (double spaced), 3 figure

Zooarqueologia dos mamíferos aquáticos e semi-aquáticos da Ilha de Santa Catarina, sul do Brasil

<abstract language="eng">This study analyzes the use of aquatic mammals by prehistoric societies of Santa Catarina Island, Southern Brazil. Samples from two archaeological sites were examined: Rio do Meio (RM) and Porto do Rio Vermelho (SCPRV). Nine aquatic mammal species were found: a) pinnipeds: Arctocephalus australis (Zimmerman, 1783) and A. tropicalis (Gray, 1872), and b) cetaceans: Eubalaena australis (Desmoulins, 1822), Delphinus delphis Linnaeus, 1758, Stenella frontalis (Cuvier, 1829), Steno bredanensis (Lesson, 1828), Tursiops truncatus (Montagu, 1821), Pontoporia blainvillei (Gervais & d'Orbigny, 1844) and a non-identified rorqual from the genus Balaenoptera Lacépède, 1804. Three especies of semi-aquatic mammals were also recorded: Hydrochoerus hydrochaeris (Linnaeus, 1758), Tapirus terrestris (Linnaeus, 1758) and Lontra longicaudis (Olfers,1818). Both sites presented similar species diversity, although abundance was greater at the most recent site (RM). There were more samples from axial skeletons, but in genera the anatomical regions were homogeneously distributed among the identified taxa

Evaluation of planar silicon pixel sensors with the RD53A readout chip for the Phase-2 Upgrade of the CMS Inner Tracker

The Large Hadron Collider (LHC) at CERN will undergo an upgrade in order to increase its luminosity to $7.5 \times 10^{34}$ cm$^{-2}$s$^{-1}$. The increased luminosity during this High-Luminosity running phase\\ (HL-LHC), starting around 2029, means a higher rate of proton-proton interactions, hence a larger ionizing dose and particle fluence for the detectors. The current tracking system of the CMS experiment will be fully replaced in order to cope with the new operating conditions. Prototype planar pixel sensors for the CMS Inner Tracker with square $50 \mu$m $\times \; 50 \mu$m and rectangular $100 \mu$m $\times \; 25 \mu$m pixels read out by the RD53A chip were characterized in the lab and at the DESY-II testbeam facility in order to identify designs that meet the requirements of CMS at the HL-LHC. A spatial resolution of approximately 3.4$\mu$m (2$\mu$m) is obtained using the modules with $50 \mu$m $\times \; 50 \mu$m ($100 \mu$m $\times \; 25 \mu$m) pixels at the optimal angle of incidence before irradiation. After irradiation to a 1 MeV neutron equivalent fluence of $\Phi_{\rm eq} = 5.3 \times 10^{15}$ cm$^{-2}$, a resolution of 9.4$\mu$m is achieved at a bias voltage of 800 V using a module with $50 \mu$m $\times \; 50 \mu$m pixel size. All modules retain a hit efficiency in excess of 99\% after irradiation to fluences up to $2.1 \times 10^{16}$ cm$^{-2}$. Further studies of the electrical properties of the modules, especially crosstalk, are also presented in this paper.The Large Hadron Collider at CERN will undergo an upgrade inorder to increase its luminosity to7.5 × 10$^{34}$ cm$^{-2}$s$^{-1}$. The increased luminosityduring this High-Luminosity running phase, starting around 2029,means a higher rate of proton-proton interactions, hence a largerionizing dose and particle fluence for the detectors. The currenttracking system of the CMS experiment will be fully replaced inorder to cope with the new operating conditions. Prototype planarpixel sensors for the CMS Inner Tracker with square50 μm × 50 μm and rectangular100 μm × 25 μm pixels read out by theRD53A chip were characterized in the lab and at the DESY-II testbeamfacility in order to identify designs that meet the requirements ofCMS during the High-Luminosity running phase. A spatial resolutionof approximately 3.4 μm (2 μm) is obtained using themodules with 50 μm × 50 μm(100 μm × 25 μm) pixels at the optimalangle of incidence before irradiation. After irradiation to a 1 MeVneutron equivalent fluence ofΦ$_{eq}$ = 5.3 × 10$^{15}$ cm$^{-2}$, a resolution of9.4 μm is achieved at a bias voltage of 800 V using a modulewith 50 μm × 50 μm pixel size. All modulesretain a hit efficiency in excess of 99% after irradiation tofluences up to 2.1 × 10$^{16}$ cm$^{-2}$. Further studies ofthe electrical properties of the modules, especially crosstalk, arealso presented in this paper.The Large Hadron Collider (LHC) at CERN will undergo an upgrade in order to increase its luminosity to $7.5 \times 10^{34}$ cm$^{-2}$s$^{-1}$. The increased luminosity during this High-Luminosity running phase (HL-LHC), starting around 2029, means a higher rate of proton-proton interactions, hence a larger ionizing dose and particle fluence for the detectors. The current tracking system of the CMS experiment will be fully replaced in order to cope with the new operating conditions. Prototype planar pixel sensors for the CMS Inner Tracker with square $50 \mu$m $\times \; 50 \mu$m and rectangular $100 \mu$m $\times \; 25 \mu$m pixels read out by the RD53A chip were characterized in the lab and at the DESY-II testbeam facility in order to identify designs that meet the requirements of CMS at the HL-LHC. A spatial resolution of approximately 3.4$\mu$m (2$\mu$m) is obtained using the modules with $50 \mu$m $\times \; 50 \mu$m ($100 \mu$m $\times \; 25 \mu$m) pixels at the optimal angle of incidence before irradiation. After irradiation to a 1 MeV neutron equivalent fluence of $\Phi_{\rm eq} = 5.3 \times 10^{15}$ cm$^{-2}$, a resolution of 9.4$\mu$m is achieved at a bias voltage of 800 V using a module with $50 \mu$m $\times \; 50 \mu$m pixel size. All modules retain a hit efficiency in excess of 99% after irradiation to fluences up to $2.1 \times 10^{16}$ cm$^{-2}$. Further studies of the electrical properties of the modules, especially crosstalk, are also presented in this paper

Beam test performance of a prototype module with Short Strip ASICs for the CMS HL-LHC tracker upgrade

International audienceThe Short Strip ASIC (SSA) is one of the four front-endchips designed for the upgrade of the CMS Outer Tracker for the HighLuminosity LHC. Together with the Macro-Pixel ASIC (MPA) it willinstrument modules containing a strip and a macro-pixel sensorstacked on top of each other. The SSA provides both full readout ofthe strip hit information when triggered, and, together with theMPA, correlated clusters called stubs from the two sensors for useby the CMS Level-1 (L1) trigger system. Results from the firstprototype module consisting of a sensor and two SSA chips arepresented. The prototype module has been characterized at theFermilab Test Beam Facility using a 120 GeV proton beam

Evaluation of HPK n+n^+-pp planar pixel sensors for the CMS Phase-2 upgrade

International audienceTo cope with the challenging environment of the planned high luminosity upgrade of the Large Hadron Collider (HL-LHC), sched-uled to start operation in 2029, CMS will replace its entire tracking system. The requirements for the tracker are largely determinedby the long operation time of 10 years with an instantaneous peak luminosity of up to 7.5 × 1034 cm−2 s−1 in the ultimate perfor-mance scenario. Depending on the radial distance from the interaction point, the silicon sensors will receive a particle fluencecorresponding to a non-ionizing energy loss of up to Φeq = 3.5 × 1016 cm−2. This paper focuses on planar pixel sensor design andqualification up to a fluence of Φeq = 1.4 × 1016 cm−2.For the development of appropriate planar pixel sensors an R&D program was initiated, which includes n+-p sensors on 150 mm(6”) wafers with an active thickness of 150 μm with pixel sizes of 100 × 25 μm2 and 50 × 50 μm2 manufactured by Hamamatsu.Single chip modules with ROC4Sens and RD53A readout chips were made. Irradiation with protons and neutrons, as well was anextensive test beam campaign at DESY were carried out. This paper presents the investigation of various assemblies mainly withROC4Sens readout chips. It demonstrates that multiple designs fulfill the requirements in terms of breakdown voltage, leakagecurrent and efficiency. The single point resolution for 50 × 50 μm2 pixels is measured as 4.0 μm for non-irradiated samples, and6.3 μm after irradiation to Φeq = 7.2 × 1015 cm−2